eds an ITIN, Form W-7 and documents, resident vs nonresident, key 2027 dates and free IRS help.
By Ruben Sevumyants, founder of Pomogu
Your first U.S. tax season raises many questions: SSN or ITIN, which form, what if I only arrived last year? Here are the basics for tax year 2026, based on what the IRS and state tax departments publish.
This is general information, not legal or tax advice.
If you are eligible for a Social Security number, you use your SSN for taxes. The IRS says green card holders, people with a U.S. work visa and anyone else eligible for an SSN do not need an ITIN.
An ITIN (Individual Taxpayer Identification Number) is a 9-digit number the IRS issues to people who have a federal tax purpose but are not eligible for an SSN. For example, you must file a return, want a refund, or are claimed as a spouse or dependent. You can apply regardless of immigration status.
An ITIN is for federal taxes only. It does not authorize work, does not change immigration status, does not qualify you for Social Security benefits or the Earned Income Tax Credit, and is not ID outside the tax system.
You cannot have both numbers. If you later get an SSN, stop using the ITIN and notify the IRS so it can combine your tax records under the SSN.
An ITIN application package has three parts:
Form W-7, Application for IRS Individual Taxpayer Identification Number. Every family member who needs an ITIN fills out a separate W-7.
Your federal tax return (Form 1040 or 1040-NR). Leave the SSN field blank for each ITIN applicant; the IRS writes in the number once it is assigned. Do not file the return separately.
Supporting documents proving identity and foreign status.
Apply by your return's due date. You can request an extension (Form 4868) without an ITIN by writing "ITIN TO BE REQUESTED" in the number field.
A valid passport is the only document that proves both identity and foreign status on its own.
Without a passport, you need two documents from the IRS list (such as a national ID card, USCIS photo ID, U.S. visa or birth certificate), one with a photo.
Documents must be originals or certified copies from the issuing agency, and not expired on the day you apply.
The IRS does not accept notarized copies.
Dependents generally must also prove U.S. residency (for example, a passport with a U.S. entry date, or school or medical records).
If you mail originals, the IRS says it can take up to 60 days to get them back.
You can mail the package, or apply in person and get most documents back the same day:
IRS Taxpayer Assistance Center (TAC) with ITIN services: free. Staff review your W-7 and authenticate most documents but don't help fill it out. Book ahead: the IRS says an appointment can take several weeks.
VITA site with ITIN services: free, at limited locations. Agents there help complete the W-7 and may prepare your return if you qualify.
Certifying Acceptance Agent (CAA): IRS-approved and fee-based; completes your W-7 and authenticates most documents.
Acceptance Agent: fee-based, but cannot authenticate documents, so they still go to the IRS by mail.
The IRS says to allow 7 weeks for a response, or 9 to 11 weeks during tax season (January 15 to April 30) or if you apply from abroad. Notice CP565 means your ITIN was assigned; CP566 asks for more information; CP567 is a rejection.
If an ITIN is not used on a federal return for three consecutive tax years, it expires on December 31 after the third year. Renew only if it will appear on a federal return: file a new W-7, check "Renew an existing ITIN" and follow the same steps. Filing with an expired ITIN can delay processing and reduce your refund.
Tax residency is separate from immigration status. A non-citizen is a resident alien for tax purposes if they pass either test:
Green card test: you were a lawful permanent resident during the year.
Substantial presence test: you were physically in the U.S. at least 31 days this year and at least 183 days over three years, counting all days this year, one-third of last year's days and one-sixth of the days from the year before.
Days as a student, teacher or trainee on certain F, J, M or Q visas generally don't count (file Form 8843). In the year you arrive, you may be a nonresident for part of the year and a resident for the rest, a "dual-status" return. IRS Publication 519 explains these cases.
Resident aliens file Form 1040 (or 1040-SR) and are taxed like citizens, on worldwide income.
Nonresident aliens file Form 1040-NR and generally report only U.S. income. Income from a U.S. job or business is taxed at regular rates; certain other U.S. income is taxed at a flat 30% unless a treaty lowers it.
February 1, 2027: employers must give you your 2026 Form W-2.
April 15, 2027: the deadline to file your 2026 return and pay any tax due.
October 15, 2027: the extended deadline if you filed Form 4868 by April 15. An extension gives you more time to file, not more time to pay.
Nonresidents who had no wages subject to U.S. withholding and no U.S. office or place of business generally have until June 15 to file Form 1040-NR.
IRS Free File: guided software from IRS partners, free if you qualify. On the IRS page right now, the income limit is $95,000 or less in adjusted gross income, and Free File reopens in January 2027. Start at irs.gov/freefile, not a company's own website.
VITA (Volunteer Income Tax Assistance): free preparation by IRS-certified volunteers, generally for people earning about $70,244 or less and for limited-English speakers. Services vary by site.
New York, New Jersey and Pennsylvania each have their own income tax:
New York: full-year residents use Form IT-201. Nonresidents with New York income, and people who moved in or out during the year, use Form IT-203.
New Jersey: you generally must file if gross income was over $10,000 (single or married filing separately) or $20,000 (joint or head of household). Similar rules apply to part-year residents and nonresidents.
Pennsylvania: residents, part-year residents and nonresidents file a PA-40 if PA gross taxable income was over $33, even if no tax is due.
ITIN overview: irs.gov/individuals/individual-taxpayer-identification-number
How to apply for an ITIN: irs.gov/tin/itin/how-to-apply-for-an-itin
ITIN supporting documents: irs.gov/tin/itin/itin-supporting-documents
Renewing an ITIN: irs.gov/tin/itin/how-to-renew-an-itin
IRS local offices (TAC): irs.gov/help/contact-your-local-irs-office
Substantial presence test: irs.gov/individuals/international-taxpayers/substantial-presence-test
Publication 519, U.S. Tax Guide for Aliens: irs.gov/publications/p519
IRS Free File: irs.gov/freefile
VITA: irs.gov/individuals/free-tax-return-preparation-for-qualifying-taxpayers
New York: tax.ny.gov
New Jersey: nj.gov/treasury/taxation
Pennsylvania: pa.gov/agencies/revenue
Ruben Sevumyants, Pomogu — pomogusa.com